保持珊瑚礁生機(jī)的創(chuàng)造性技術(shù)
We've heard plenty about the rapid and dramatic loss of coral reefs over the last decades. According to some estimates, as much as half of the world's coral has already disappeared in the last 30 years alone. Parts of Australia's Great Barrier Reef had lost more than 70 percent of their coral by 2016, and some scientists are calling coral loss an extinction-level event.
在過(guò)去的幾十年里,我們已經(jīng)聽(tīng)說(shuō)了很多關(guān)于珊瑚礁迅速和急劇消失的事情。據(jù)估計(jì),僅在過(guò)去30年里,世界上多達(dá)一半的珊瑚已經(jīng)消失。到2016年,澳大利亞大堡礁的部分地區(qū)已經(jīng)失去了超過(guò)70%的珊瑚,一些科學(xué)家稱(chēng)珊瑚的消失是一個(gè)滅絕級(jí)別的事件。
Coral is not only beautiful and colorful; it also provides a large number of ecosystem services. (Photo: Jolanta Wojcicka/Shutterstock)
Scientists are now scrambling for ways to save what's left of Earth's coral reefs, brainstorming and testing a wide range of strategies. Many of those ideas are collected in a pair of reports from the U.S. National Academies of Sciences, Engineering and Medicine, released in November 2018 and June 2019. As the reports point out, human help may "buy time" for coral reefs, but truly saving them will require addressing the main existential threat they face: climate change.
科學(xué)家們現(xiàn)在正在努力尋找拯救地球上僅存的珊瑚礁的方法,集思廣益,并對(duì)各種策略進(jìn)行測(cè)試。2018年11月和2019年6月,美國(guó)國(guó)家科學(xué)院、工程院和醫(yī)學(xué)院發(fā)布了兩份報(bào)告,收集了其中的許多觀點(diǎn)。報(bào)告指出,人類(lèi)的幫助可能為珊瑚礁“贏得時(shí)間”,但真正拯救它們將需要解決它們面臨的主要生存威脅:氣候變化。
In the meantime, here are a few of the tactics scientists are considering to help coral survive and reproduce for as long as possible.
與此同時(shí),以下是一些科學(xué)家正在考慮的策略,以幫助珊瑚盡可能長(zhǎng)時(shí)間地生存和繁殖。
1. Cloud brightening
云層增白
Cloud brightening could protect coral reefs by deflecting harmful solar radiation. (Photo: nicolas poizot/Shutterstock)
To save coral reefs in the ocean, one oceanographer is looking to the skies for help. Dr. Daniel Harrison is working on a method called "cloud brightening," which would use clouds to essentially provide a protective barrier over coral reefs.
為了拯救海洋中的珊瑚礁,一位海洋學(xué)家正在向天空尋求幫助。丹尼爾·哈里森博士正在研究一種名為“云層增白”的方法,這種方法將利用云層為珊瑚礁提供一個(gè)保護(hù)屏障。
Cloud brightening involves pumping sea water through a filter and using a fan to spray the water toward the clouds. The water would evaporate in the sky, but the salt particles in the water would stay behind and condense with other water — therefore making clouds appear brighter. The theory is that brighter clouds would deflect the sun's rays, which would keep the ocean water temperature cooler and in turn hopefully prevent coral reefs from bleaching and dying.
云層增白包括通過(guò)過(guò)濾器抽取海水,并用風(fēng)扇將水噴向云層。水會(huì)在天空中蒸發(fā),但水中的鹽顆粒會(huì)留在后面,與其他水凝結(jié)——因此使云看起來(lái)更亮。他們的理論是,較亮的云層會(huì)使太陽(yáng)光線(xiàn)偏轉(zhuǎn),從而使海水溫度保持較低,從而有希望防止珊瑚礁漂白和死亡。
2. Assisted evolution
輔助進(jìn)化
Coral fragments that can survive in hotter, more acidic water are replanted on reefs in hopes they'll propagate new coral. (Photo: Debra James/Shutterstock)
This method uses coral fragments and relies on a survival of the fittest approach, focusing on those that can tolerate, survive and even thrive in hotter, more acidic water.
這種方法使用珊瑚碎片,并依賴(lài)于適者生存的方法,重點(diǎn)是那些能夠忍受、生存,甚至在更熱、更酸的水中茁壯成長(zhǎng)的珊瑚。
A team of scientists in the Florida Keys break off pieces of coral and submerge them in hot, acidic water tanks. The fragments that survive are attached to artificial "trees" underwater so they can continue to grow before being transplanted back to the reef from which they were taken. It's a painstaking process that involves replanting each individual fragment one-by-one.
佛羅里達(dá)群島的一組科學(xué)家將珊瑚碎片分離出來(lái),并將其放入熱的酸性水箱中。幸存下來(lái)的碎片附著在水下的人造“樹(shù)”上,這樣它們可以繼續(xù)生長(zhǎng),然后再被移植回它們被取走的珊瑚礁。這是一個(gè)艱苦的過(guò)程,包括一個(gè)接一個(gè)地重新種植每個(gè)單獨(dú)的碎片。
3. Genetic selection
基因選擇
Scientists found that corals in the Red Sea might be naturally heat-resistant and able to survive temperatures several degrees higher than normal. (Photo: Svetlan/Shutterstock)
Retrotransposons, also known as "jumping genes," are genes that replicate and mutate. In 2017, researchers from King Abdullah University of Science and Technology in Saudi Arabia discovered genes associated with heat resistance in the symbiotic algae that live within corals. In theory, the genes would make the algae more heat-tolerant, and if the algae can survive higher temperatures, the hope is that corals would, too.
逆轉(zhuǎn)錄轉(zhuǎn)座子,也被稱(chēng)為“跳躍基因”,是復(fù)制和突變的基因。2017年,沙特阿拉伯阿卜杜拉國(guó)王科技大學(xué)的研究人員在珊瑚體內(nèi)的共生藻類(lèi)中發(fā)現(xiàn)了與耐熱性相關(guān)的基因。從理論上講,基因會(huì)使藻類(lèi)更耐熱,如果藻類(lèi)能在更高的溫度下生存,珊瑚也有希望。
4. Gene storage banks
基因儲(chǔ)存銀行
This is what bleached coral looks like. (Photo: Ethan Daniels/Shutterstock)
"We need to be gathering this genetic diversity and trying to help while there's still a lot of diversity in place in the ocean," Mary Hagedorn, a senior research scientist at the Smithsonian Conservation Biology Institute, who's based in Kaneohe, Hawaii, told NPR's Science Friday.
“我們需要收集這種基因多樣性,并試圖在海洋中仍然有很多多樣性的時(shí)候提供幫助,”瑪麗·哈格多恩告訴NPR的《科學(xué)星期五》,她是位于夏威夷卡內(nèi)奧赫的史密森保護(hù)生物學(xué)研究所的高級(jí)研究科學(xué)家。
It's encouraging that all this work is ongoing. "We created these problems," Michael P. Crosby, president of the Mote Marine Laboratory & Aquarium in Sarasota, Florida, told The New York Times. "We have to get actively involved in helping the corals come back."
令人鼓舞的是,所有這些工作都在進(jìn)行中。“我們制造了這些問(wèn)題,”佛羅里達(dá)州薩拉索塔莫特海洋實(shí)驗(yàn)室和水族館的總裁邁克爾·p·克羅斯比告訴《紐約時(shí)報(bào)》。“我們必須積極參與幫助珊瑚回歸。”
But while there is renewed hope and action for corals, it would obviously be simpler (not to mention less costly), to mitigate global warming and water pollution now.
然而,雖然珊瑚有了新的希望和行動(dòng),但現(xiàn)在減輕全球變暖和水污染顯然會(huì)更簡(jiǎn)單(更不用說(shuō)成本更低)。